Flexible Low-Temperature Heat Storage for Heat Pump with Predictive control

Abstract

Heat pumps are increasingly popular all over the world. There is a general effort to increase the coefficient of performance. One of the options to increase this coefficient is to utilize auxiliary technologies. In this paper, two of such applicable technologies are tested: low-temperature storage in conjunction with predictive control, allowing the heat pump to operate with a minimum temperature difference. The idea is that, based on the outside temperature, the heat pump low-temperature source of heat is switched between the outdoor air temperature and the water temperature in the low-temperature storage. The paper is proposing a predictive algorithm for storage charging and discharging control based on the outside temperature. In this way, the heat pump can provide heating water for the heated object with a variable temperature currently required by the heating system of the object. The historical record of air temperature values in the city of Brno, Czech Republic, are used for the evaluation of the predictive control function. By applying the proposed predictive control, an increase in Seasonal Coefficient of Performance of 16.65 % was achieved compared to the basic operating state.